Piston ring



July 19; 1927.-

J. A. OLSON ET AL PISTON RING Filed May 17, 1926 avwcutow attorney Iline 8-8 of Fi Patented July 19, 1927.

UNITED {STATES PATIENT. OFFICE.

JOHN A. OLSON AND ERNEST R. HELLMAN, OF DETROIT, MICHIGAN.

PISTON RING.

Application filed Kay 17,

, relates to piston rings for internal combustion engines and more particularly to a type designed for preventing oil pumping by the piston.

n the present state of the art it is common practice to provide thepiston with a ring groove at the lower end of the 'skirt in which aslotted ring is inserted, the slots serving to convey some of the excesslubricant into the space behind the ring from whence it is allowed todrain into the inte-. rior of the piston through holes drilled in thepiston walls. One of the objects of our invention is to provide animproved type of slotted piston rin which will more effectually preventthe lubricant passing the ring. Another object is to provide a modifiedconstruction having provision allowing a limited amount of oil to bedelivered above the ring for the purpose of lubricating the portion ofthe piston above the same. These and other objects are attained by thenovel construction as hereinafter set The invention features of forthand illustrated in the accompanying drawings, wherein:

Figure 1 is a bottom plan view partly in section of one form of ourinvention.

Figure 2 is a side view thereof.

Figure 3 is an enlarged section on the line 3-3 of Figure 1 also showingthe arrangement of the ring in the groove of the piston.

Figure 4 is a similar section on the line 4-4 of Figure 1.

Figure 5 is a top plan view of a modified construction'shown partly insection.

Figure 6 is a side elevation thereof.

Figure 7 is an enlar ed cross section thereof on the line 7-7 of Figure5.

Figure 8 is a similar cross section on the gure 5.

Referring now to the embodiment of the invention illustrated in Figures1 to 4 and designated as the oil stop ring, A represents the ring itselfof the usual split type, B and B the overlapping ends of the ring and Ga series of slots extending through the ring from the outer to the innersurfaces. The slots are preferably milled into the ring and aretherefore of slightly greater extent on the outer surface than on theinner our.- face. The lower surface D of the ring has formed therein agroove E the outer Surface:

1926. Serial No. 109,741.

E of which is of conical form and inclined ring is also provided with abeveled surface- H between the upper end I and the outer cylindricalsurface F.

he ring as above described is inserted in the piston ring groove J inthe usual manner and the plston wall K is provided with a. downwardlyinclined bore L extendmg from the inner surface of the piston to thelower corner of the groove J. As stated above it is usual to place theoil stop ring in the lowermost groove in the piston while in the head ofthe piston is provided with the usual type of sealing ring.

In the operation of a piston provided with the improved oil stop ring,the oil adboring to the cylinder walls is allowed to pass by the outercylindrical surface F of the ring on the upward stroke of the piston andthis action is facilitated by the beveled upper surface H. On thedownward stroke of the piston the lubricant is scraped from the cylinderwalls by the sharp annular lower edge of the ring andcollects in thegroove E from whence it is passed through the inclined bores G into theslots C. The 011 then collects in the portion of the ring groove behindthe piston ring and flows downwardly through the bore L into theinterior of the piston from whence'it is drained back into the crankcase. Thus the construction as above described is very effective inpreventing lubricant from'passing by the ring and'entering the portionof the cylinder above the piston.

In certain motors the piston ring of the tyipe above described would beentirely too e ective in reventing passage of oilabove the ring andmightin some cases result in insuflicient lubrication of the piston headand the piston rings arranged therein. We have therefore devised amodified form of ring which permits a limited amount of oil to passthrough the ring in order to insure the proper lubrication of thecylinder walls and the piston head. struction is illustrated in Figures5 to 8 wherein the ring is constructed similarly to the one previouslydescribed except that the drilled holes G communicate only with thealternate slots C the other slots not being connected to the undersideof the ring. In the modified construction it is also preferio able toomit the beveled edge H and instead also having a drilled parent that ofhaving a lain upper edge for the ring, it is provide with an annulargroove intermediate the inner and outer surface of the ring andpreferably spaced from the same. The ring is then provided with thedrilled holes N extending from the groove M through the ring into theslots C, the ar rangement being such that the alternate slots are incommunication with the opposite ends of the piston ring;

In the operation of a piston provided with the modified form of ring theoil is scraped from the cylinder walls in the same manner as previouslydescribed, but a certain amount of the lubricant which is collected inthe'ring groove J behind the pistonring is carried upward through theslots C and apertures N to the upper groove M. from which point acertain amount is thrown out by inertial forces and lubricates thecylinder walls above the piston ring.

From the above description it will be apwe have devised two improvedtypes of piston rings, one of which is particularly adapted for motorswhere there is a tendency for excessive oil pumping and the other ofwhich is designed for motors where the first type would preventthenecessary lubrication of the piston head.

What we claim as our invention is:

1. A piston ring provided with a sharp annular lower edge adapted tocontact with the cylinder Wall, a series of slots extending through thering between the outer and innor surfaces thereof and a drilled holeextending from a point adjacent said edge to one of said slots.

2. A piston ring having a slot extending therethrough from the outer tothe inner surface, having an annular groove in the lower surface thereofand having a drilled hole extending between said groove and said slot.

3. A piston ring having an annular groove in the lower ed e thereofforming in cross section a V shape notch the outer surface of whichintersects the outer cylindrical surface of the ring at an acute an 1e,said ring having slots extending outwar ly from the inner surface ofsaid ring between the upper and lower edges of said ring, said ring holeinclined upwardly from said groove and intersecting with said slot.

4. A piston ring having a slot extending This modified conan annularoutwardly from the inner surface of the ring and having a drilled holebetween said slot and the upper surface of said ring.

5* A piston ring having a groove in its upper edge and having anaperture extending from the inner surface of the ring to the saidgroove.

6. A-piston ring having a slot extending from the inner to the outersurface, having a groove in its upper edge and having a dlrilled holebetween said groove and said s ot. c

7. A pistonring provided with a sharp annular lower edge adapted tocontact with the cylinder wall, an aperture extending from a pointadjacent said edge through said ring to the inner cylindrical surfacethereof and an aperture extending through the ring between said innercylindrical surface and the upper edge of the ring.

8. A piston ring having a series of Separate slots extendingtherethrough intermediate the upper and lower edges, an apertureextending from one of said slots to the lower surface of said ring andan aperture extending from another of said slots to the upper surface ofsaid ring.

9. A piston ring having a series of slots extending from the inner tothe outer surface, said ring having the lower edge provided with anannular groove, the outer surextending outwardly from the inner cylindrical surface, said ring also having a series of drilled holescommunicating with said slots, the holes from the alternate slots leading res ectively to the upper and lower edges 0 the ring. 11. Thecombination with a piston havmg an annular groove therein, of a pistonring inserted in said groove, said ring being provided with means forcollecting the oil' from the cylinder walls in said groove beh nd saidrlng, and said ring being also provided with a restricted passagewayextendmg from the inner surface thereof to the upper surface whereb alimited amount of lubricant ma pass t rough said ring to a point above te same. 1

12. The combination with a piston having groove therein, of a pistonring engagin sald groove and space from the lnner cy indrical surfacethereof, said ring being provided with a passageway extending 7 anannular groove therein, of a piston ring engaging said groove, the saidring being provided with means for collecting the oil from the cylinderwalls and with means cooperating with the said groove for conducting aportion ofthe collected oil to the upper surface of the ring.

14:. The combination with a piston having an annular groove therein, ofa piston ring engagingsaid groove, the said ring having an oilcollecting groove in its lower edge and an oil receiving groove in itsupper edge, the said ring be'ng further provided with means cooperatingwith the groove in the piston for conducting oil from its oil collectinggroove to its oil receiving groove.

15. The combination with a piston ring having a slot extending outwardlyfrom its inner surface, of means for supplying oil to said slot, andmeans for conducting oil from the slot to the upper edge of the ring.

In testimony whereof we afiix our signatures.

JOHN A. OLSON. ERNEST R. HELLMAN.

